Radiator Type: Air-cooled Application Laptop Size: 18 Type: Six Fans USB Ports: 2 Material: Aluminum & Plastic Heat-Dissipating Method: Air-Cooled USB Interface: 2 (Supports Input and Output) Board Material: Metal Mesh Product Size: 26.5*36*2.8cm Noise: 21- 23dbA Input Interface: USB 5V Output Power: 4.5W The Rotational Speed of the Fan: 2000- 2400 10%